Quantitative Pill Analysis

Didn't have a chance to fully read through it, but it looks like quantitative pill analysis may be on the way (as opposed to qualitative GC/MS) or I could have it wrong?
but check it out here - http://www.sciencedirect.com/scienc...id=37161&md5=a0a438a9d472e8ff4474a29d725b7911
EDIT: Looks like rather than being "on the way" the technology exists. Interesting findings.

Yeah that's a research paper - it takes a long time to go from there to analytical technique, but I can see what they're trying to do.

The upshot of the article is they're trying to use reflectance and transmittance of near infrared radiation to analyse the content of tablets, with the aim of being able to analyse evidence non-destructively. It seems from their conclusion that at this stage, the whole tablet analysis has more potential for error than the crushed tablet analysis.

One of the most interesting parts of this article for me was the results of their conventional "reference" liquid chromatography studies:

After pulverizing the seized ecstasy samples the amphetamines being in the illicit tablets were determined by liquid chromatography. The analysis of the samples showed that there was only one active per tablet. No mixtures of amphetamine homologues could be found. The tablets containing amphetamine additionally all contained caffeine as additive. The range of the contents of the actives with regard to the different amphetamine groups were 54.54–94.18 mg for MDMA, 54.74–85.89 mg for MDE and 19.65–31.79 mg for amphetamine, respectively.

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It's always good to get reliable figures on confiscated street ecstacy, I think. I don't know how much faith to put in their calibration method, because I haven't looked into IR spec for a looong time. I guess it's all part of establishing the protocols for testing - quite often these analytical techniques spit out unphysical measurements related to observable quantities, which must then be processed to get useful answers. I don't know enough about the processing they have to do to comment on whether this technique will ever make it into R&D.

BigTrancer

A couple of other interesting papers:

Composition profiling of seized ecstasy tablets by Raman spectroscopy

http://www.rsc.org/CFmuscat/intermediate_abstract.cfm?FURL=/ej/AN/2000/b005662f.PDF

FULL PDF (free)

http://pubs.rsc.org/ej/AN/2000/b005...125</b>&Fp=1811&Ep=1815&JournalCode=AN&Iss=10

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Optimization of extraction parameters for the chemical profiling of
3,4-methylenedioxymethamphetamine (MDMA) tablets]

http://www.rhodium.ws/pdf/mdma.impurity.extraction.optimization.pdf

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Doesn't it worry you that effective dosage of MDMA is around one point to 120 mg and all those pills are significantly under that????

What do you mean by 'effective'? The threshold dose for MDMA to begin having an effect is more like 30mg, according to Erowid. Maybe you mean 'ideal', based on an often quoted figure of approximately 2mg/kg body weight?

BigTrancer

Most pills you're getting are sub 100mg I can guarentee it.

Providing all the amines present in a sample can be extracted, there is a way to estimate the total nitrogen in the sample and therefore (theoretically) roughly calculate the quantitative level of amines present, based on averaging the molecular weights of likely constituents. Using the possible amines; MDMA, MDA MDEA MDBD PMA PMMA it should be possible to gauge this to around 20% accuracy. If one could be certain [?] of the mixture of amines i.e. only MDMA & MDA, accuracy could be improved to around 8% error (for this example).

The technique, known as Kjeldahl Analysis, can be applied in several ways. It basically works by converting the amine to a free ammonium ion (NH4+) Concentration is calculated by either releasing the NH4+ as ammonia gas and titrating it against a quantity of HCl, or forming a salt (usually sulphate) and titrating that. As the amount of nitrogen present represents a percentage of the weight of the amine, the total amount is easily calculated.

The approach has 2 major problems. One is that the initial N digestion has to be carried out using a lengthy distillation, or using a bomb in a microwave. Both have obvious disadvantages for the average user.
The second problem is of course identifying each amine separately or at least indicating what mixture is in the sample.

This has been the area I've been looking at lately, reviewing different approaches to determining actual amines present as well as looking at ways in which to simplify procedures. Lots to be done, so any input welcome

Of course, while often employed in estimating cocaine concentration, freebasing extracted amines allows a fairly accurate estimation of total amine content (using the above - averaging MWs of suspected amines)
You must then do the simple math to get an accurate result.

Some time in the future I'll start a thread which reviews all tried and tested methods, including the other end of things; GC/ MS/ HPLC, etc etc. and colorimetric analysis which may hold the key to a future user friendly affordable, and sufficiently accurate process